Oxazolo-{8 4,5-b{9 -pyridine-2-ones and -2-thiones as intermediates

ABSTRACT

New sulphur containing phosphorus compounds of pyrido-oxazole derivatives, their manufacture and use as pesticides are disclosed. The new compounds correspond to the formula   WHEREIN R1 represents halogen or nitro, R2 represents hydrogen or lower alkyl, R3 represents alkyl, alkoxy, alkenyloxy, alkynyloxy, phenyl, amino, monoalkylamino or dialkyl-amino, R4 represents alkyl, alkenyl or alkynyl, and X and Y each represent oxygen or sulphur.

United States Patent Kristinsson et al.

[ 51 Dec. 30, 1975 OXAZOLO-[4,5-B]-PYRIDINE-2-ONES AND -2-THIONES ASINTERMEDIATES Inventors: Haukur Kristinsson, Bottmingen;

Kurt Rufenacht, Basel, both of Switzerland Assignee: Ciba-GeigyCorporation, Ardsley,

Filed: Oct. 7, 1974 Appl. No.: 512,787

Related US. Application Data Continuation of Ser. No. 435,066, Jan. 21,1974, abandoned, which is a division of Ser. No. 156,983, June 25, 1971,Pat. No. 3,808,218, which is a continuation-in-part of Ser. No. 155,604,June 22, 1971, abandoned.

Foreign Application Priority Data June 26, 1970 Switzerland 9702/70 US.Cl... 260/294.8 C; 260/295 K; 260/295 F;

260/294.8 K; 424/200 Int. Cl. C07D 213/44 Field of Search 260/295 K,294.8 C

References Cited UNITED STATES PATENTS 5/1961 Brahler et al. 260/307 CFOREIGN PATENTS OR APPLICATIONS 713,278 8/1954 United Kingdom 260/307 CPrimary Examiner-Alan L. Rotman Attorney, Agent, or FirmFrederick H.Rabin 57] ABSTRACT New sulphur containing phosphorus compounds ofpyrido-oxazole derivatives, their manufacture and use as pesticides aredisclosed. The new compounds correspond to the formula 17 Claims, NoDrawings DESCRIPTION THE INVENTION The present invention relates to neworganic phosphorus compounds, processes for their manufacture,insecticidal and acaricidal preparations that contain these newcompounds and their usein combating animal and vegetable pests,

The new organic phosphorus compounds correspond to the formula wherein Rrepresents hydrogen, halogen or nitro, R represents hydrogen, methyl,chloromethyl or bromomethyl, R represents alkyl, alkoxy, alkenyloxy,alkynyloxy, alkoxyalkoxy, halogenalkoxy, phenyl, amino, monoalkylaminoor dialkylamino, R represents alkyl, alkenyl, alkynyl, alkoxyalkyl orhalogenoalkyl and X and Y each represents oxygen or sulphur.

For R representing halogen, fluorine, chlorine, bromine or iodine, butespecially chlorine or bromine, are suitable.

Alkyl, alkenyl or alkynyl chains that are possible for R and R containas lower hydrocarbon radicals or as the hydrocarbon part of alkoxy,alkenyloxy, alkynyloxy, alkoxyalkoxy and alkylamino radicals R and R atthe most 6, preferably at the most 4, carbon atoms and may be straightor branched.

Exemplary of such radicals are, interalia, methyl, ethyl, n-propyl,isopropyl, n-, i-, sec.-, tert.-butyl, allyl, crotonyl, methallyl,propargyl, n-butynyl.

Particular importance attaches to compounds of the formula 1 wherein Rrepresents hydrogen, chlorine, bromine or nitro, R has the meaning givenunder formula I above, R represents an alkyl, alkoxy, alkenyloxy,alkoxyalkoxy, or halogenoalkoxy radical, each radical R containing atthe most 4 carbon atoms, or a phenyl radical, amino radical ordialkylamino radical with 2 to 4 carbon atoms, R represents an alkyl,alkenyl, alkoxyalkyl or halogenoalkyl radical with at the most 4 carbonatoms and X and Y represent oxygen or sulphur.

The compounds of the formula I are manufactured by reacting anoxazolo(4,5 )pyridine derivative of the formula 1 vwherein A representsthe halogenmethyl radical, the

vinyl group or a 1,2-dihalogenethyl radical, with a phosphorus compoundof the formula optionally in the presence of an acid binding agent, orwith asalt thereof. in the formulae III and IV, the symbols R to R.,, Xand Y, have the meanings given for formula I.

The phosphorus compounds of the formula IV react with the oxazolo(4,5)pyridine derivatives of the formula 111 without further difficulties attemperatures between 0 and 120C, preferably at l0to C. It is advisableto carry out the process according to the invention in the presence of asolvent or diluent that is inert towards the reactants. Possiblesolvents or diluents are primarily aliphatic ketones, such as acetone,methyl ethyl ketone; alkanols such as methanol, ethanol, isopropanol;esters, such as ethyl acetate; nitriles; N-alkylated acid amides;aromatic hydrocarbons, such as benzene, toluene and water, and mixturesof such solvents with water.

The reaction of a compound of the formula III, in which A representshalogen-methyl or 1,2-dihalogenmethyl, with a compound of the formula IVtakes place accompanied by the exchange of the, or a, halogen atom; inthe process, the halogen atom in the 1-position in the1,2-dihalogen-ethyl radical is exchanged. The reaction is thereforecarried out by adding acid binding agents or with salts, especially withalkali metal salts and ammonium salts of the phosphorus compounds of theformula III. Preferred acid binding agents are the alkali metalhydroxides and carbonates; however, tertiary nitrogen bases can also beused. If A represents the vinyl group, the phosphorus compound of theformula IV adds on to the vinyl double bond.

As examples of possible starting meaterials of the formula III, thefollowing may, inter alia, be considered for the process according tothe invention:

3 -chloromethyl-oxazolo 4 ,5 -b pyridin-2-( 3 H )-oneBchloromethyl-oxazolo[4,5-b]pyridin-2(3l-l)-thione3-chloromethyl-6-chloro-oxazolo[4,5-b]pyridin- 2(3l-I)-one3-bromomethyl-6-chloro-oxazolo[4,5-b]pyridin- 2(3l-I)-one3-chloromethyl-6-bromo-oxazolo[4,5-blpyridin- 2(3I-I)-one3-chloromethyl-6-nitro-oxazolo[4,5 -b lpyridin- 2(3I-I)-one3-vinyl-oxazolo[4,5-b]pyridin-2(3I-I)-one3-vinyl-oxazolo[4,5-b]pyridin-2(3H)-thione3-vinyl-6-chloro-oxazolo[4,5-b]pyridin-2(3l-I)-one3-vinyl-6-bromo-oxazolo[4,5-b]pyridin-2(3H)-one3-vinyl-6-nitro-oxazolo[4,5-b]pyridin-2(3H)-one3-(1,2-dichloroethyl)-oxazolo[4,5-b]pyridin-2- (3H)-one3-(1',2'-dibromoethyl)-oxazolo[4,5-b]pyridin- 2(3I-I)-0ne 3-(1,2-dichloroethyl)-oxazolo[4,5-b]pyridin- 2(3l-l )-thione 3-(1,2-dibromoethyl)-oxazolo [4 ,5 -b] pyridin- 2(31-1 )-thione 3-(1',2-dichloroethyl-6-chloro-oxazolo [4 ,5 -b] pyridin-2(3H)-one 3-( l,2'-dibromoethyl)-6-chloro-oxazolo[4,5-b]pyri- 3-( l,2'-dichloroethyl)-6-bromo-oxazolo[4,5-b]pyri- 3-(1,2'-dibromoethyl)-6-bromo-oxazolo[4,5-b]pyridin -2(3H)-one 3-(1',2'-dichloroethyl)-6-nitro-oxazolo[4,5-b]pyridin-2(3H)-one 3-( l',2'-dibromoethyl)-6-nitro-oxazolo[4,5-b]pyridin-2(3l-I)-one Thefollowing thiophosphoric acids, thiophosphonic acids and thiophosphoricamides may be mentioned, inter alia, as examples of phosphorus compoundsof the formula IV:

0,0-dimethyl-dithiophosphoric acid 0,0-dimethyl-monothiophosphoric acid0,0-diethyl-dithiophosphoric acid 0,0-diethyl-monothiophosphoric acid0,0-di-isopropyl-dithiophosphoric acid O-methyl-O-ethyl-dithiophosphoricacid O-methyl-O-isopropyl-dithiophosphoric acidO-methyl-O-isopropyl-dithiophosphoric acid 0,0-diallyl-dithiophosphoricacid 0,0-bis-(Z-methoxy-ethyl)-dithiophosphoric acid0,0-bis-(2-ethoxy-ethyl)-dithiophosphoric acid0,0-bis-(2-chloroethyl)-dithiophosphoric acidO-methyl-dithio-rnethylphosphonic acid O-ethyl-dithio-methylphosphonicacid O-methyl-dithio-ethylphosphonic acid O-ethyl-dithio-ethylphosphonicacid O-methyl-dithio-phenylphosphonic acidO-ethyl-dithio-phenylphosphonic acid O-methyl-thiophosphoric acid amideO-ethyl-thiophosphoric acid amide O-isopropyl-thiophosphoric acid amideO-methyl-thiophosphoric acid-methyl amide O-ethyl-thiophosphoricacid-methyl amide O-methyl-thiophosphoric acid-ethyl amideO-ethyl-thiophosphoric acid-ethyl amide O-methyl-thiophosphoricacid-dimethyl amide O-ethyl-thiophosphoric acid-dimethyl amideO-methyl-thiophosphoric acid-diethyl amide O-ethyl-thiophosphoricacid-diethyl amide O-methyl-dithiophosphoric acid-dimethyl amideO-ethyl-dithiophosphoric acid-dimethyl amide O-methyl-dithiophosphoricacid-diethyl amide O-ethyl-dithiophosphoric acid-diethyl amideO-isopropyl-dithiophosphoric acid-dimethyl amide The phosphoruscompounds of the formula IV can be manufactured according to knownprocesses.

The starting materials of the formula [II have not been describedhitherto. The oxazolo(4,5-b)-pyridine derivatives of the formula III, inwhich A represents a halogen-methyl radical, are manufactured byconverting an oxazolo (4,5-b)pyridine of the formula V R I l I Crivatives. As halogenating agents there may be used: thionyl chloride,phosphorus trichloride and phosphorus tribromide, phosphoruspentachloride and phosphorus pentabromide, phosphorus oxyhalides, etc.Since in the case of these oxazolo[4,5-b]pyridines there occurs no saltformation with the hydrogen halide that is split off, the addition of anacid binding agent can be dispensed with.

The starting materials of the formula III, in which A represents thevinyl group of a 1,2-dihalogen-ethyl radical, are obtained by reactingan oxazolo[4,5- b]pyridine of the formula IV with vinyl acetate in thepresence of mercury slats of strong acids [l-l. Hopff et al., Helv.chim. Acta 18, 135-140(19601to give the corresponding3-vinyl-oxazolo[4,5-b]pyridine derivatives. It is also possible,moreover, to obtain such compounds by splitting off 3-(2'-hydroxyethyl)and 3-(2'- acetoxyethyl) derivatives) by heating or by reacting anoxazolo [4,5-b]pyridine of the formula V with acetylene. The3-(1',2'-dihalogenethyl)-oxazolo[4,S-b]pyridine derivatives are thenobtained by the addition of halogen, such as chlorine or bromine, to thevinyl group.

These reactions are carried out preferably in a solvent or diluent thatis inert, or in solvent mixtures that are inert, towards the reactants.The hydroxymethyl group is introduced advantageously in an aqueousmedium; the subsequent halogenation to the halogenmethyl group, likewisethe addition of halogen to the vinyl group, in a halogenatedhydrocarbon, such as chloroform, carbon tetrachloride, halogenatedethylenes and the like. In addition, aromatic hydrocarbons such asbenzene, chlorobenzene and the like can also be used. 7

The reaction temperatures are in the range from 0 to C. The startingmaterials of the formula III are obtained in good yield and purity. Theycan be used directly for the reactions according to the inventionwithout further purification.

The oxazolo[4,5-b]pyridine-2(3H)-ones represented by formula IV can betheoretically in a tautomeric form, represented by the formula IVa, asoxazolo[4,5- b]pyridine-2(4H )-ones. In this case, the acid NI-I-groupwould therefore be in the pyridine ring, instead of in the oxazolo ring.The claimed compounds of the formula 1 could accordingly also be writtenas 4-substituted isomers, corresponding to an alternative formula la.However, since all claimed compounds and all their primary productsalways occur only in a single form, they are cited here for reasons ofconsistency and simplicity as 3-substituted isomers, both by formula andnomencla- The compounds of the formula I are suitable for combatingvarious animal and vegetable pests. They are particularly suitable forcombating insects and representatives of the order Acarina. These activesubstances have a good to very good contact action and ingested actioncombined with systematic action, and are of particular importance incombating insects that eat plants and such the juice of plants,representatives of the order Acarina, as well as the development stagesof these pests. By such pests are to be understood in particular thosethat belong to the following families:

Acrididae:

Phloeothripidae: Miridae:

Piesmidae: Lygaeidae: Pyrrhocoridae: Jaxsidae:

Psyllidae: Aleyadidae: Aphididae:

Eriosomatidae:

Pseudoococcidae:

Lecaniidae: Stictococeidae: Diaspididae: Tenthredinidae:

Silphidae: Chrysomelidae:

Curcuionidae:

Scolytidae:

Scarabaeidae:

Pyralidae: Pyraustidae: Crambidae: Schoenabiidae: Tortricidae:

Gelechiidae:

Gracilariidae: Lyonetiidae:

Geometridae:

L mantriidae:

octuidae:

e.g. e.g. e.g.

Locusta spp. Schistocerca spp. Heliothrips haem. Distantiella theobromaSahlbergella singularis Piesma quadrata Lygus spp. Dysdercus spp.Cicadula spp. Typhlocyba spp. Empaasca spp. Psylla spp. Trialeuradesspp. Macrosiphon spp. Aphis spp.

Myzodes spp. Eriosoma spp. Planococcus citri Coccus spp. Stictococcusspp. Quadrispidiotus pern. Athalia rosae Hoplocampa spp. Blitaphagaapaca Leptinatarsus dec. Melasoma spp. Lema spp. Phyllotrela spp.Diabron'ca spp. Sitana lineata phyllobius spp. Oliorrhynchus spp.Ceutorrhynchus spp. Anthonamus spp. Phytonomus spp. Cylas spp.

Apion spp.

Scolylus spp, Dendraclanus spp. Blaslophagus spp. Hypothenemus hampeiMelalomha spp. Rhizotragus spp. Pachnoda spp. Diatraea saccharalisOstrim'a nubilalis Chilo spp. Schaenobius spp. Pandemis :pp. Carbocapsapom. Grapholita spp. Epinolia spp. Conchylis ambiguella Zeirapheradim'ana Tortrix spp.

' Phthorimaea spp.

Pectinophora goss. Lithocolletis spp. Lyonetia spp. Leucoptera coff.

H yponomeuta xpp. Argyresthia ephip. Plutella maculipennis Acrolepiaassectella Hepialus spp.

Pieris spp. Campsilia spp. Operiphlhera spp. Erannis spp. Selenia spp.Lymantria dispar Spadoptera linoralis Heliathis zea Mamestra spp. Scotiaspp. Orthosia spp.

Trypetidae:

Drosophilidae:

Agromyzidae:

Chldropidae:

Muscidae:

Tarsonemidae:

Tetranychidae:

Eriophyidae:

-continued e.g. Ceratitis capitata Dacus oleae e.g. Drosophila spp.

e.g. Phytamyza rufipes Agromyza megalopsis Saptomyza flaveola e.g.Oscinis frit Chloraps spp.

e.g. Hylemya brassicae Hylemya antiqua Hylemya flaralis Pegomyahyoscyani e.g. Tarsonemus fragaria e.g. Tetranychus urticae Panonychusulmi e.g. Eriophyes rjbis Aceria sheldoni Phyllocoptrupa oleivorusMuscidae:

Calliphoridae:

Gastraphilidae: Hypodermatidae:

Hippoboscidae: Oestridae: Tabanidae: Culicidae:

Simuliidae: Lipeuridae: Phthiriidae: Pediculidae: Pulicidae:

Tungidae: Argasidae:

lxodidae:

Dermanyssidae:

Musca domestica Stomoxys calcitrans Calliphora erythrocephala Luciliacuprina Callitroga hominivorax Gastmphilus ihtestinalis Hypaderma bovisDermatobia irritans Melophagus ovinus Oestris ovis Tabanus bovinusAnopheles spp.

Culex spp. Aedes spp. Simulium sericatum Lipeurus baculus (Mallophag)Phthirus pubis Pediculus corporis Crenoeephalides. canis Ctenacephalidesfelis Tunga penelrans Ornithodorus moubata Argus reflexus' Ixodesricinus (ii-phase) Dermacentbr reticulatus (3 -phase) Rhipicephalusspec. (Z-phase) Rhl'picephalus appendiculatus Rhipicephalus everbiBoophilus microplus l-phase) Boophilus decoloratus Amblyoma spec.Dermanyssus gallinae Bdellonysrus bacoti Demodex canis Trombicula aulumnalis Sarcaptes spp.

Psoroptes spp.

In admixture with other insecticides or acaricides, the activityspectrum of the active substances according to the invention can bebroadened and, in particular, the insecticidal and acaricidal actionimproved. Exemplary of suitable additives for broadening the action are,for example: insecticidal and/or acaricidal esters and amides ofphosphoric acid, phosphonic acid, thioand dithiophosphonic acid,halogenated hydrocarbons and and analogues of DDT active substance, aswell as pyethrines, esters of halobenzilic acid, oxicarba- 7 mates,arylcarbamates and and carbamates of enolisable heterocycles.

Some of the new phosphorus compounds of the formula I are furthersuitable for combating endoparasites, especially parasitic helminths andtheir development stages such, for example, as representatives of thefamilies Ascaridae, Trichostrongylidae, Ancylostanatidae, in domesticand farm animals such as cattle, sheep, goats, horses, pigs, cats, dogsand poultry.

The active substances are non-toxic in the concentrations used forcombating endoparasites, and are very well tolerated by domestic andfarm animals.

The active substances of the formula I can be used as pure activesubstance or together with suitable carriers and/or additives. Suitablecarriers and additives may be solid or liquid and correspond to thesubstances conventionally used in formulation technique.

The preparations according to the invention are manufactured in knownmanner by intimately mixing and grinding the active substances of theformula I together with suitable carriers, optionally with the additionof dispersing agents or solvents that are inert towards the activesubstances. The active substances can be in the form of and used in thefollowing preparations:

Solid preparations:

dusting agents, scattering agents, granulates, coated granulates,impregnated granulated granulates and homogeneous granulates;

liquid preparations:

a. active substance concentrates that are dispersable in water: wettablepowders, pastes, emulsions;

b. solutions.

To produce dusts, scattering agents and granulates the active substancesare mixed with solid carriers. Examples of carriers which can beemployed are kaolin, talcum, bole, loess, chalk, limestone, groundlimestone, Attaclay, dolomite, diatomaceous earth, precipitated silicicacid, alkaline earth silicates, sodium and potassium aluminum silicates(feldspar and mica), calcium and magnesium sulfates, magnesium oxide,ground synthetic plastics, fertilizers such as ammonium phosphates,ammonium nitrate, urea, ground vegetable products such as bran, barkdust, sawdust, ground nutshells, cellulose powder, residues of plantextractions, active charcoal, etc. These carriers can be used alone oradmixed with each other.

The particle size of the carriers is, for dusts advantageously up toabout 0.1 mm, for scattering agents from about 0.075 to 0.2 mm, and forgranulates 0.2 mm or coarser.

The concentrations of active substance in the solid preparations areusually from 0.5 to 80%.

To these mixtures can also be added additives which stabilize the activesubstance and/or non-ionic, anionic and cationic surface activesubstances, which for example improve the adhesion of the activeingredients on plants or parts of plants (adhesives and agglutinants)and/or ensure a better wettability (wetting agents) and dispersibility(dispersing agents). Examples of suitable adhesives are the following:olein/chalk mixture, cellulose derivatives (methyl cellulose,carboxymethyl cellulose), hydroxyethyl glycol ethers of monoalkyl anddialkyl phenols having to ethylene oxide radicals per molecule and 8 to9 carbon atoms in the alkyl radical, lignin sulfonic acids, their alkalimetal and alkaline earth metal salts, polyethylene glycol ethers(carbowaxes) fatty alcohol polyethylene glycol ethers having 5 toethylene oxide radicals per molecule and 8 to 18 carbon atoms in thefatty alcohol moiety, condensation productsof ethylene oxide/propyleneoxide, polyvinyl pyrrolidones, polyvinyl alcohols, condensation productsofur'ea and formaldehyde, and also latex mazes- 11 v s later-djspersible concentrates of the active substance, i.'e'. wettablepowders, pastes and emulsifiable concentrates, are agents which can bediluted with water to any concentration desired. They consist of activesubstance, carrier, optionally additives which stabilize the activesubstance, surface-active substances and anti-foam agents and,optionally, solvents. The concentration of active substance in theseagents is 5 to Wettable powders and pastes are obtained by mixing andgrinding the active substances with dispersing agents and vpulverulentcarriers in suitable apparatus until homogeneity is attained. Carriersare, for example, those mentioned for the solid forms of application. Insome cases it is advantageous to use mixtures of different carriers. Asdispersing agents there can be used, for example, condensation productsof sulfonated naphthalene and sulfonated naphthalene derivatives withformaldehyde, condensation products of naphthalene or naphthalenesulfonic acids with phenol and formaldehyde, as well as alkali, ammoniumand alkaline earth metal salts of lignin sulfonic acid, in addition,alkylaryl sulfonates, alkali and alkaline earth metal salts of dibutylnaphthalene sulfonic acid, fatty alcohol sulfates such asv salts orsulfated hexadecanols, heptadecanols, octadecanols, and salts ofsulfated fatty alcohol glycol ethers, the sodium salt of oleoylethionate, the sodium salt of oleoyl methyl tauride, ditertiaryacetylene glycols, dialkyl dilauryl ammonium chloride and fatty acidalkali and alkaline earth metal salts.

Suitable anti-foam agents are silicones.

The active substances are so mixed, ground sieved and strained with theadditives mentioned above that, in wettable powders, the solid particlesize of from 0.02 to 0.04 and in pastes, of 0.03 is not exceeded. Toproduce emulsifiableconcentrates and pastes, dispersing agents such asthose given in the previous paragraphs, organic solvents and water areused. Examples of suitable solvents are the following: alcohols,benzene, xylenes, toluene, dimethyl sulfoxide, and mineral oil fractionsboiling'between 120 and 350C. The solvents must be practically odorless,not phytotoxic, inert to the active substances and not readilyinflammable.

Furthermore, the agents according to the invention can be applied in theform of solutions. For this purpose the active substance or severalactive substances of general Formula I are dissolved in suitable organicsolvents, mixtures of solvents or in water. Aliphatic and aromatichydrocarbons, chlorinated derivatives thereof, alkyl naphthalenes, andmineral oils, alone or mixed with each other, can be used as organicsolvents. The solution should contain the active substances in aconcentration of from 1 to 20%.-

The preparation according to the invention may also be mixed, forexample, with fungicides, bactericides, fungistatics, bacteriostatics ornematocides, in addition to the insecticides and acaricides, in order tobroaden the activity spectrum; The preparations according to theinvention may also contain plant fertilisers, trace elements etc.

The content of active substance in the above described preparationsvaries from 0.1 to and in this connection it should be mentioned that onapplication 9 from an aircraft or by some other suitable means ofapplication, concentrations of up to 99.5% or even pure active substancemay be used.

In the Examples that follow, preparations of the new active substancesof the formula I are described. The parts denote parts by weight.

Dusting agentsz The following substances are used for manufacture of (a)a and (b) a 2% dusting agent:

5 parts of active substance of the formula I; e.g. 0,0-

dimethyl-S-6-chloro-oxazolo(4,5-b)-pyridin- 2(3H)-onyl-(3)-methyl)dithiophosphate. parts of magnesium carbonate 85parts of talcum 2 parts of 0,0-diethyl-S-(6-chloro-oxazolo(4,5-b)pyridin-2(3l-l) -onyl-(3-)methyl)-dithiophosphate 1 part of highlydispersed silica 97 parts of talcum The active substances are mixed withthe carriers.

Granulate:

The following substances are used to manufacture a 5% granulate: i

5 parts of the active substance of the formula I, e.g.

0,0-diethyl-S-(6-chloro-oxazolo(4,5-b)pyridin-2(3H)-onyl-(3-)methyl)-dithiophosphate 0.5 parts of the epoxidisedvegetable oil l part of highly dispersed silica 93.5 parts of kaolin(0.4 0.8 mm particle size) The active substance is mixed with thevegetable oil and the silica and dissolved in 6 parts of acetone. Theresulting suspension is sprayed onto kaolin and the acetone subsequentlyevaporated in vacuo.

Wettable Powder The following constituents are used to manufacture (a) a40%, (b) a 50%, (c) a 25% and (d) a 10% wettable powder:

40 parts of active substance of the formula I, e.g.

0,0-dimethyl-S-(oxazolo(4,5-b)pyridin-2(3ll)- onyl-( 3 )-methyl)-dithiophosphate 5 parts of the sodium lignin sulphonate l part of thesodium dibutyl naphthyl sulphonate 54 parts of silica b.

50 parts of the active substance of the formula I, e.g.

0,0-diethyl-S-(oxazolo(4,5-b)pyridin-2(3H)- onyl( 3)-methyl-dithiophosphate 5 parts of alkylaryl sulphonate (Tinovetin B)10 parts of calcium lignine sulphonate 1 part of Champagnechalk-hydroxyethyl cellulose mixture (1:1) I

parts of silica 14 parts of kaolin;

parts of the active substance of the formula 1, e.g.

0,0-diethyl-S-(6-chloro-oxazolo(4,5-b) pyridin-2(3H)-onyl-(3)-methyl)-thiophosphate 3 parts of a mixture of the sodiumsalts of saturated fatty alcohol sulphates 1 5 parts ofnaphthalenesulphonic acid/formaldehyde concentrate 82 parts of kaolin.

10 The active substances are intimately mixed with the additives insuitable mixers and ground on mills and rollers. Wettable powders areobtained which can be diluted with water to form suspensions of anydesired concentration.

Emulsifiable concentrate The following constituents are mixed togetherto manufacture (a) a 10% and (b) a 20% emulsifiable concentrate:

10 parts of active substance of the formula I, e.g. 0,0-dimethyl-S-[6-chloro-oxazolo[4,5-b]-pyridin- 2( 3 H )-onyl-( 3 )-methyl-dithiophosphate 10 parts of a composite emulsifier (fatty alcoholpolyglycolether and ethyl arylsulphonate) 40 parts ofdimethylcyclohexylphthalate 40 parts of tetralin; b.

20 parts of active substance of the formula 1, e.g.

0,0-diethyl-S-[6-chloro-oxazolo[4,5-b]-pyridin- 2 3 H )-onyl-( 3)-methyl ]-dithiophosphate 20 parts of dioxane 10 parts of a compositeemulsifier (fatty alcohol I polyglycolether and alkylaryl sulphonate) 50parts of tetralin. This concentrate can be diluted with water to formemulsions of any desired concentration.

Spray: The following constituents are used to manufacture (a) a 5% and(b) a 2% spray:

5 parts of active substance of the formula I, e.g. 0,0-

dimethyl-S-[oxaxolo[4,5-b]pyridin-2( 3H )-onyl- (3 )-methyll-dithiophosphate 1 part of epichlorohydrin 94 parts of petroleum ether(boiling limits dimethyl-S-[6-chloro-oxazolo[4,5-b]-pyridin- 2( 3H)-ony1-( 3 )-methyll-dithiophosphate 3 parts of4,4'-dichlorodiphenyl-trichloroethane 95 parts of kerosene.

These solutions are sprayed with a pressure sprayer.

Anti-helminthic preparations of the new phosphorus compounds of theformula I are described herewith below. The parts denote parts byweight.

Active substance concentrate in paste form:

Such semisolid or oily active substance concentrates have, for example,the following composition:

40 parts of active substance of the formula I, e.g.

0,0-diethyl-S-[6-chloro-oxazolo[4,5-blpyridin- 2(3H )-onyl-( 3 )-methyll-dithiophosphate 10 parts of bolus alba 2 parts of sodium ligninsulphonate 0.2 parts of sodium benzoate 1.0 part of carboxymethylcellulose 46.8 parts of water;

30 parts of active substance of the formula I, e.g.0,0-bis-(2'-chloroethyl)-S-[oxazolo[4,5-b]-pyridin-2( 3H )-onyl-( 3)-methyl]-dithiophosphate parts of ground-nut oil.

The active substances are very finely ground with the carriers,dispersants and other additives (particle size 5-10 microns).

Powder concentrate 2 parts of active substance of the formula I, e.g.0,0-

1 1 The following substances are used to manufacture (a) a 50% and (b) a25% powder concentrate:

50 parts of active substance of the formula I, e.g.

0,0-diethyl-S-[oxazolo[4,5-b]pyridin-2(3H)-onyl- (3)-methyl]-dithiophosphate 3 parts of polyoxyethylene-sorbitan-monooleate3 parts of sodium lignin sulphonate 44 parts of bolus alba;

25 parts of active substance of the formula I, e.g.

0,0-diethyl-S-[oxazolo[4,5-b]pyridin-2(3H)-thione-3-yl-methyl]-dithiophosphate 8 parts of polyvinyl pyrrolidone 3parts of dodecylbenzenesulphonate 39 parts of diatomaceous earth 30parts of bolus alba.

The indicated active substances are applied to the carriers, for examplein the form of acetonic solutions. The dispersants and wetting agentsare added subsequently and the concentrate is ground to homogeneity.

EXAMPLE 1 a. 109 Grams of oxazolo[4,5-b]pyridine-2-(3l-l)-one J. Frazerand E. Tittenser, J. Chem. Soc. (London) 1957, 4625 are stirred in amixture of 100 g of approx. 37% aqueous formaldehyde solution and 600 mlof water for one-half hour at room temperature and for one-half hour at5060C. After cooling, filtration and drying to filtrate, 126 g of3-hydroxymethyloxazolo[4,5-b]pyridine-2(3l-l)-one are obtained (m.p.155C, with decomp.).

b. 126 Grams of 3-hydroxymethyl-oxazolo[4,5- b]pyridine-2-(3H)-one aresuspended in 1200 ml of chloroform. 126 Grams of thionyl chloride arerun in rapidly, the mixture is stirred initially for half an hour atroom temperature, then for 3 hours at 60C, cooled and the undissolvedimpurities are filtered off. The

filtrate is evaporated to dryness in a water jet vacuum, the residuemixed with petroleum ether and filtered, to yield 126 g of3-chloromethy1-oxazolo[4,5-blpyridine- 2(3H)-one' (m.p. 10911lC).

c. 18.5 Grams of 3-chloromethyl-oxazolo[4,5-b1pyridine-2(3l-l)-one and21 g of the ammonium salt of 0,0-dimethyl-dithiophosphate are stirred in100 ml of acetone for 4 hours at 35C. 100 Milliliters of water are addedand the acetone is distilled off in a water jet vacuum at 35C. Thecrystals that have separated out 'are filtered off and recrystallisedfrom methanol, to

yield 20 g of 0,0-dimethyl-S-[oxazolo[4,5-b]-pyridine- 2(3 H )-onyl-( 3)-methyll-dithiophosphate (m.p. 70-71C).

Calc.: N, 9.15; P, 10.1; S, 20.9%.

Found: N, 9.3; P, 10.0; S, 20.9%.

EXAMPLE 2 12 Found: C, 39.55; H, 4.55; N, 8.48; P, 9.19; S, 19.25%.

EXAMPLE 3 t 63 Grams of the potassium salt of 0,0-bis-(2-methoxy-ethyl)-dithiophosphoric acid and 37 g of 3- chloromethyl-oxazolo[4,5-b]pyridine-2(3H)-one are stirred in 300 ml of acetone for 4 hoursat 40C. The solvent is then distilled off in a water jet vacuum, theresidue treated with 300 ml of water, and the oil that has separated outis taken up in ether. The ether solution is washed with sodiumbicarbonate and water, dried, and the ether is distilled off. Theresidual oil is freed from volatile fractions by heating to C in a highvacuum and subsequently filtered through an animal charcoal filter.

63 Grams of0,0-bis-(2methoxy-ethyl)-S-[oxazolo-4,5-b]pyridine-2(3H)-onyl-(3)-methyl]-dithiophosphate are obtained in the form of a pale yellow,nondistillable oil, which is a single substance in thin-layerchromatogram.

Calc.: C, 39.59; H, 4.86; N, 7.10; P 7.87; S, 16.26%.

Found: C, 40.0; H, 4.9; N, 6.9; P, 7.7; S, 16.2%.

EXAMPLE 4 49 Grams of O-ethyl-dithio-phenylphosphonic acid and 37 g of3-chloromethyl-oxazolo[4,5-b]pyridine- 2(3H)-one are dissolved in 200 mlof acetone. While stirring, a solution of 9 g of sodium hydroxide in 40ml of water is added dropwise and the mixture is then heated for 4 hoursto 35C. The acetone is distilled of in a water jet vacuum, the residuetreated with 200 ml of water and extracted with ether. The etherealextract is washed until neutral, dried and distilled off, to leave arapidly congealing oil. Recrystallisation from 300 ml of methanolyields, 37 g of O-ethyl-S-[oxazolo[4,5- b]pyridins-2(3H)-onyl(3)-methyl]-ditliio phenylphosphate Calc.: C, 49.16; H,4.13; N, 7.64; P, 8.47; S,17.50%.

Found: C, 49.10; H, 4.20; N, 7.61; P, 8.66; S, 17.20%.

EXAMPLE 5 a. 204 Grams of oxazolo[4,5-b]pyridine-2(3l-l)-one aredissolved in 1500 ml of dime'thylformamide. At 20-25C, 111 g of chlorineare introduced into the solution within 2 hours. The mixture is furtherstirred for 1 hour and poured into 3 liters of ice water. The productthat has crystallised out is filtered off, washed and dried. 212 Gramsof 6-chloro-oxazo1o[4,5-b]pyridine-2-(3H)-one (m.p. 187-188C) are.obtained.

b. Grams of 6-chloro-oxazolo[4,5-b]pyridine-2- (3l-l)-one, 800 m1 ofwater and g of an approx. 37% aqueous formaldehyde solution are stirredfor one-half hour at room temperature and then for 2 hours at 50-60C.The mixture is cooled, the precipitate that forms filtered off, theresidue washed with ice water and dried at 40C in a water jet vacuum.148 Grams of 3-hydroxymethyl-6-chloro-oxazolo[4,5-b]pyridine-2(3l-l)-one (m.p. 138C, with decomp.) are obtained.

c. 200 grams of'thionyl chloride are rapidly run into a suspension of240 g of 3-hydroxymethyl-6-chlorooxazolc-[4,5-b]pyridine-2(3l-l)-one in1200 ml of chloreform. The mixture is stirred for one-half hour at roomtemperature, then for 1 hour at 60C. The by this 13 time clear solutionis evaporated to dryness in a water jet vacuum, the residue treated withpetroleum ether, filtered and dried. In this manner, 238 grams of 3-chloromethyl-6-chloro-oxazolo[4,5-b]pyridine- 2(3 H)-one(rn.p. 104106C)are obtained.

d. 44 Grams of 3-chloromethyl-6-chlorooxazolo[4,5-b]-pyridine-2(3H)-oneand 49 g of the ammonium salt of 0,0-diethyl-monothiophosphoric acid arestirred in 300 ml of acetone for 4 hours at 60C. The acetone isdistilled off in a water jet vacuum and the residue treated with 300 mlof water. The crystalline precipitate that has formed is filtered offand recrystallised from methanol. 42 Grams of 0,0-diethyl-S-[6-chloro-oxazolo[4,5-b]pyridine2(3 H)-onyl-(3)-methyl]-dithiophosphate are obtained 5 961C).

Ca1c.: C, 37.45; H, 4.00; N, 7.95; P, 8.80; S, 9.09%.

Found: C, 37.63; H, 4.10; N, 8.03; P, 8.70; S, 9.23%.

EXAMPLE 6 A solution of 238 g of3-chloromethyl-6-chlorooxazolo[4,5-b]pyridine-2(3H)-one in 500 ml ofacetone is slowly added dropwise to a suspension of 255 g of thepotassium salt of 0,0-dimethyl-dithiophosphoric acid in 500 ml ofacetone. The temperature gradually rises to 32C and the mixture isfurther stirred for 4 hours at 30C. The solvent is thereafter strippedoff in a water jet vacuum, the residue treated with 100 ml of water, andthe oil that has separated out is taken up in ether. The ether solutionis washed with sodium hydrogen bicarbonate solution and with water andthe ether is dried and distilled. The residue congeals to crystallineform. Recrystallisation from 500 ml of methanol yields, 198 g of0,0-dimethyl-S-[6-chlorooxazolo[4,5-b]pyridine-2(3H)-methyl]-dithiophosphate(m.p. 7 880C).

Calc. C, 31.72; H, 2.96; N, 8.23; P, 9.1 1; S, 18.82; Cl, 10.41%.

Found C, 31.38; H, 2.95; N, 8.28; P, 8.89; S, 18.53; Cl, 10.63%.

EXAMPLE 7 166 Grams of the potassium salt of0,0-diethy1-dithiophosphoric acid and 135 g of 3-chloromethyl-6-chloro-oxazolo[4,5-b]pyridine-2(3H)-one are dissolved in 800 ml ofacetone. The temperature of the reaction mixture slowly rises to 33C.600 Milli1iters of water are then added and the bulk of the acetone isdistilled off in a water jet vacuum at 35C. The oil that has initiallysettled out congeals to crystalline form. Recrystallisation from 500 mlof methanol yields 170 g of0,0-diethyl-S-6-chloro-oxazolo[4,5-b]pyridine- 2(3H)-onyl-(3)-methyl]-dithiophosphate (m. p. 81- 82 C).

Calc.: C, 35.82; H, 3.83; N, 7.60; P, 8.42; S, 17.39; Cl, 9.62%.

Found: C, 35.85; H, 3.80; N, 7.64; P, 8.31; S, 17.34; Cl, 9.97%.

EXAMPLE 8 42 Grams of 0,0-bis-(2-chloroethyl)-dithiophosphoric acid and35 g of 3-chloromethyl-6-chlorooxazolo[4,5-b]pyridine-2(3H)-one aredissolved in 150 ml of acetone. A solution of 6.5g of sodium hydroxidein 65 ml of water is then added dropwise and the mixture is stirred for4 hours at 40C.

The acetone is thereafter distilled off in a water jet vacuum, 300 ml ofwater are added and the oily crystalline precipitation that forms istaken up in ether. The ether solution is washed with sodium bicarbonatesolution and with water. Recrystallisation twice from a small amount ofmethanol yields 22 g of 0,0-bis-(2-chloroethyl)-S-[6-chloro-oxazolo-[4,5-b]pyridine- 2(3H )-onyl-( 3)-methyl]-dithiophosphate (m .p. 71-73C.

Calc.: C, 30.18; H, 2.76; N, 6.40; P, 7.09; S, 14.69; Cl, 24.30%.

Found: C, 30.23; H, 2.79; N, 6.20; P, 6.96; S, 14.72; C1, 24.28%.

EXAMPLE 9 45 Grams of O-methyl-dithio-phenylphosphonic acid aredissolved in 200 ml of acetone. A solution of 9 g of sodium hydroxide in400 ml of water is then added dropwise. Thereafter 44 g'of Ex. 5 (c) areintroduced and the reaction mixture is' stirred for 4 hours at 35C.

The acetone is then distilled off in a water jet vacuum,

2 3 H )-onyl-( 3 )-methyl ]-dithio-phenylphosphate (m .p.

Calc.: C, 43.47; H, 3.13, N, 7.24; P, 8.02; S, 16.57; C1,.9.17%.

Found: C, 43.41; H, 3.24; N, 6.97; P, 8.03; S, 16.52; Cl, 9.25%.

EXAMPLE 10 a. 204 Grams of oxazolo 4,5-b pyridine-2-(3H)-one aredissolved in 1500 ml of dimethylformamide. 264 Grams of bromide areslowly added dropwise at room temperature, the mixture is stirred for 1hour and poured into 9 liters of ice water. The crystalline product thatforms is filtered off and dried in vacuo at 50C, yielding 249 g of6-bromo-oxazolo[4,5- b]pyridine-2(3H)-one (m.p. 230-232C).

b. 173 Grams of 6-bromo oxazolo[4,5-b]-pyridine- 2(3H)-one, 900 ml ofwater and 100 g of an approx. 37% aqueous formaldehyde solution arestirrred for one-half hour at room temperature and then for 1 hour underreflux. The mixture is cooled, the precipitate that forms is filteredoff, washed with ice water and dried at 40C in vacuo, yielding 184 g of3-hydroxymethyl-6- bromoxazolo[4,5-b]pyridine-2(3H)-one (decomp. at C;with splitting off of formaldehyde).

0. 133 Grams of thionyl chloride are run rapidly into a suspension of183 g of 6-bromo-oxazolo[4,5-b]-pyridine-2-(3H)-one in 1500 ml ofchloroform. The mixture is stirred for one-half hour at room temperatureand then for 2 hours at 60C. The by now clear solution is evaporated todryness in a water jet vacuum, the residue mixed with petroleum,filtered off and dried,

15 yielding 192 g of3-chloromethyl-6-bromooxazolo[4,5-b]pyridine-2(3H)-one (m.p. 129130C).d. 1 16 Grams of 3-chloromethyl -6-bromo-oxazolo[4,5-b]pyridine-2(3H)-one and 1 19 g of the potassium salt of0,0-diethyldithiophosphoric acid are stirred for 4 hours at 35C in 600,1 of acetoneThe acetone is then distilled off in vacuo and the residuetreated with 600 ml of water. The oil that has separated out congeals toa crystalline form after it has been thoroughly stirred.Recrystallisation from methanol yields 136 g of 0,0-diethyl-S-[6-bromo-oxazolo[4,5-b]pyridine-2(3H)-onyl-(3)-methyl]dithiophosphate (m.p. 98-99C).

Calc.: C, 31.97; H, 3.42; N, 6.78; P, 7.51; S, 15.52

Found: C, 32.09; H, 3.37; N, 6.87; P, 7.36; S, 15.48

Calc: Br, 19.33

Found: Br, 19.88

EXAMPLE 1 l A solution of 26.4 g of3-chloromethyl-6-bromooxazolo[4,5-b]pyridine-2(3H)-one in 190 ml ofacetone are added dropwise to a suspension of the potassium salt of0,0-dimethyldithiophosphoric acid in 40 ml of acetone and the mixture issubsequently stirred for 4 hours at room temperature. Precipitatedpotassium chloride is filtered off and the filtrate evaporated in awater jet vacuum. The residual oil is stirred with a small amount ofmethanol until it crystallises. Recrystrallisation from 160 ml ofmethanol yields 23.5 g of 0,0-dimethyl-S-[6-bromo-oxazolo[4,5-b]pyridin-2-(3H)-onyl-(3)-methyl]-dithiophosphate (m.p. 8687C).

Calc.: N, 7.27; S, 16.64; P, 8.05

Found: N, 7.3; S, 16.4; P, 7.9

EXAMPLE 12 6 Grams of the potassium salt ofdi-isopropyl-dithiophosphoric acid and 53 g of3-chloromethyl-6-bromooxazolo [4,5-b]pyridine-2(3H)-one are stirred in300 ml of acetone for 4 hours at 35C. The acetone is distilled off awater jet vacuum, the residue treated with 300 ml of water, and the oilthat has separated out taken up in ether. The ethereal solution iswashed with sodium bicarbonate solution, dried and the ether distilledoff. The residual oil is dissolved in 120 ml of methanol. 62 Grams of0,0-diisopropyl-S-[6-bromooxazolo[4,5-b]pyridine-2-(3H)-onyl-(3)-methyl]- dithiophosphate (m.p. 6567C)crystallise on cooling.

Calc.: C, 35.37; H, 4.11;N, 6.35; P, 7.03; S, 14.53

Found: C, 35.35; H, 3.95; N, 6.31; P, 7.02; S, 14.56

Calc.: Br, 18.28

Found: Br, 19.06

By using 55 gof the potassium salt of 0,0-diallyldithiophosphoric acidand proceeding in a manner analogous to the above Example, 42 g of0,0-diallyl-S-[6- bromo-oxazolo[4,5-b] pyridin-2(3H)-onyl-(3)-methyl]-dithiophosphate are obtained (m.p. 3840C).

Calc.: C, 35.71; H, 3.22; N, 6.41; P, 7.10; S, 14.66

Found: C, 35.35; H, 3.16; N, 6.56; P, 6.85; S, 14.31

Calc.: Br, 18.28

Found: Br, 19.06

EXAMPLE 13 a. 152 Grams of oxazolo 4,5-b pyridine-2(3H )-thione [T.Takahashi & F. Yoneda, Pharm. Bull. (Tokyo) 5, 350 (1957)] in a mixtureof 140 g of a 37% aqueous formaldehyde solution and 600 ml of water arestirred for one-half hour at room temperature and subsequently for 2hours at 60C. After cooling, filtration and drying the filtrate, 180 gof 3-hydroxymethyloxazolo [4,5-b]pyridin-2(3H)-thione are obtained (noreal melting .point; splitting off of formaldehyde at 1 10C).

b. 180 g of 3-hydroxymethyl-oxazolo[4,5-b]pyridin- 2(3H)-thione aresuspended in 1500 ml of chloroform. 167 Grams of thionyl chloride arerun in at room temperature, the mixture is stirred for half an hour atthe same temperature then gradually heated to 60C and maintained at thistemperature for 2 hours. The by now clear solution is evaporated todryness, the residue stirred with petroleum ether and filtered, yielding190 g of crude 3-chloromethyl-oxazolo[4,5-b]pyridin2(3H)- thione (m.p.120123C).

c. Grams of the potassium salt of 0,0-diethyldithiophospho'ric acid and70 g of 3-chloro-methyl-oxazolo 4,5-b pyridine-2(3H)-thione aresuspended in 800 ml of acetone. The suspension is stirred for 4 hours at3540C, then the acetone is distilled off in a water jet vacuum and theresidue treated with'800 ml of water. The oil that has initiallyseparated out congeals to crystalline form. Recrystallisation from 400ml of methanol yields 87 g of 0,0-diethyl-S-[oxazolo[4,5b]pyridin-2(3H)-thi0ne-3-yl-methyl]-dithiophosphate (m.p. 6466C).

Calc: C, 37.70; H, 4.32; N, 7.99; P, 8.85; S, 27.45

Found: C, 37.43; H, 4.18; N, 7.91; P, 8.59; S, 27.78

EXAMPLE 14 30 Grams of O-methyl-dithio-methyl-phosphonic acid aredissolved in 150 m1 of acetone and treated dropwise with a solution of 9g of sodium hydroxide (solid) in 50 ml of water. 44 Grams of3-chloromethyl- 6-chloro-oxazolo[4,5-b]pyridine-2(3H)-one are introducedinto the mixture, which is stirred for 4 hours at 35C. 200 Millilitersof water are then added and the acetone is removed from the reactionmixture in a water jet vacuum. The oil that separates out initiallysolidifes to a viscous mass, which is isolated by decanting andrecrystallised directly from 400 ml of methanol, to yield 46 g ofO-methyl-S-[6- chloro-oxazolo-[4,5-b]pyridin-2(3H)-onyl-(3)methyl]-dithio-methyl-phosphonate (m.p. 7779C).

Calc.: C, 33.28; H, 3.10; N, 8.63; P, 9.56; S, 19.74; Cl, 10.92.

Found: C, 33.56; H, 2.99; N, 8.51; P, 9.54; S, 19.47; Cl, 1 1,00.

EXAMPLE 15 22 Grams of 3-chloromethyl-6-chloro-oxazolo[4,5- b]pyridine-2(3 H)-one and 19 g of O-methyl-N,N- dimethyl-dithiophosphoricacid amide are dissolved in 150 ml of acetone. A solution of 5 g ofsodium hydroxide (solid) in 25 ml of water is then added dropwise andthe mixture is stirred-for 4 hours at 40C. The bulk of the solvent issubsequently distilled off in a water jet vacuum and the residue treatedwith ml of water. The oil that has separated out is crystallised atonce. Recrystallisation from methanol yields 25 g ofO-methyl-N,N-dimethyl-S-[6-chloro-oxazolo[4,5-b]-pyridin- 2( 3 H)-onyl-( 3 )-methyl -dithiophosphoric amidate (m.p. 8991C).

Calc.: C, 33.95; H, 3.70; N, 11.89; P, 8.77; S, 18.77; C], 10.02

Found: C, 34.20; H, 3.75; N, 12.19; P, 8.66; S,

EXAMPLE 16 1 nitric acid are added dropwise at '10C and the mix-' tureis left to stand for 3 to 4 days at room temperature. The reactionmixture is then poured onto 3 kg of ice, the precipitated nitrationproduct filtered off and recrystallised from ethanol/water to yield 141g of the pale yellow 6-nitro-oxazolo[4,5-b ]pyridin-2(3H)-one (mp. 225Caccompanied by previous conversion at 200C). I

b. 90 Grams of 6-nitro-oxazolo[4;5 -b]pyridin-2-(3H)- oneare suspendedin 550 ml of water. 1 10 Millilitres of an approx. 37 aqueousformaldehyde solution are then added and the mixture-is stirred forone-half hour at room temperature and then for 2 hours at 60C.-Theresulting paste is cooled, filtered and the'filter cake cooled, filtereduntil clear and concentrated in a rotary evaporator. The oily residue istreated with ice, then crystallised. Recrystallisation from aqueousmethanol yields 54 g of 3-vinyl-oxazolo[4,5-b]pyridin-2(3H)-one (m.p.5557C).

b. 32 Grams of 3-vinyl-oxazolo[4,5-b]pyridin- 2(3H )-one and 45 g ofdiethyl-dithiophosphoric acid are disolved in 150 ml of toluene andboiled under reflux for 8 hours. The reaction mixture is then cooled,diluted with ether and shaken out with sodium bicarbonate solution andwith water. The ether-toluene solution is dried and the solvent isdistilled off. The residual oil crystallises slowly. Recrystallisationfrom 70 ml of washed with cold water. After a thorough drying in vacuoat 40C, 102 g of pale yellow 3-hydroxymethyl- 6-nitro-oxazolo[4,5-b]pyrid in-2(3H)-one are obtained, which decomposes from 140Caccompanied by splitting off of formaldehyde.

c. 106 Grams of 3-hydroxymethyl-6-nitro-oxazolo [4,5-b]pyridin-2(3H)-oneare suspended in 750 ml of chloroform. 5 Milliliters ofdimethylformamide are added and 100 g of thionyl chloride are then runin at room temperature. With gradual heating, the reaction commencesaccompanied by vigorous development of gas. After the reaction hassubsided, the mixture is boiled for 1 hour under reflux and all volatilecomponents are then distilled off in a rotary evaporator at 50C. Theresidue forms. a viscous oil or a crystalline crust. It is dissolved in150 ml of ethyl acetate, the solution is treated with 75 ml of petroleumether and filtered over animal charcoal. The clear filtrate is treatedat 45C with petroleum ether (approx. 150ml) until the onset ofturbidity. On cooling, 83 g of pale yellow3-chloromethyl-6-nitro-oxazolo[4,5-b]pyridin- 2(3H)-one cyrstallise(m.p. 107-109C).

d. 46 Grams of 3-chloromethyl-6-nitro-oxazolo[4,5- b]pyridin-2(3H)-oneand 38 g of the ammonium salt of 0,0-dimethyl-dithiophosphoric acid aredissolved in 150 ml of acetone and the solution is stirred for 4 hoursat 40C. The solvent is then distilled off in a water jet vacuum at 40C,the residue is treated with water and the oil that has separated out istaken up in ether. After being repeatedly shaken out with sodiumbicarbonate solution and with water, the ether solution is dried and thesolvent distilled off. The residual oil crystallises after a time.Recrystallisation twice from 10 times the amount of methanol .yields .26g of Q,O-dimethyl-S-[6-nitrooxazolo[4,5-b]pyridin-2(3H)-onyl-(3)-methyl]- dithiophosphate (m.p.6163C).

Calc.: C, 30.77; H, 2.87; N, 11.96; P,8.84; S, 18.25

Found: C, 30.80; H, 2.84; N, 12.04; P, 8.84; S, 18.27

EXAMPLE 17 a. To 344 g of vinyl acetate are added initially'5,.6g ofmercuryacetate andf then 0.75 g of sulphuric acid monohydrate. 65-5Grams of oxazolo[4,5-b]pyridine- 2-(3H)-one are then introduced and themixture is heated for 7 hours underhreflu x. The mixtureis henb]pyridin-2(3H )-onyl-( 3 )-ethyl-( 1 ]-dithiophosphate (m.p. 39-4lC).

Calc.: C, 41.37; H, 4.91;N, 8.04; P, 8.91; S, 18.41 Found: C, 41.68; H,5.08; N, 8.17; P, 8.90; S, 18.68

EXAMPLE 18 a. To a solution of 32.4 g of 3-vinyl-oxazolo[4,5-b]pyridin-2(3H)-one in 200 ml of carbon tetrachloride are added slowlydropwise while cooling with ice at 010C 32 g of bromine dissolved in 100ml of carbon tetrachloride. The reaction solution is filtered untilclear and evaporated in a rotary evaporator. The residual oilcrystallises on cooling. The crystallised product is triturated with 120ml of petroleum ether and filtered, to yield 57 g of3-(1,2'-dibromo-ethyl)- oxazolo[4,5-b]pyridin-2(3H)-one(m.p. 79-72C).

Calc.: C, 29.8; H, 1.85; Br, 49.7; N, 8.7; O, 9.95 Found: C, 30.0; H,1.9; Br, 49.5; N, 8.8; O, 10.0 b. 64 Grams of3-(1',2-dibromo-ethyl)oxazolo[4,5- b]pyridin-2(3H)-one and 37 g of theammonium salt of 0,0-dimethyl-dithiophosphoric acid are dissolved in 250ml of acetonitrile and stirred for 3 hours at 60C. The bulk of thesolvent is then distilled off in a water jet vacuum and the residue istreated with 200 ml of water. The oil that has separated out is taken upin ether, the

' ether solution is washed with sodium bicarbonate solu- (3H)-one aremixed together and the reaction mixture 7 tion and with water, dried,and the ether distilled off.

The residue crystallises. Recrystallisation from 55 ml of methanolyields 30 g of 0,0-dimethyl-S-[oxazolo-[4,5-b]pyridin-2(3H)-onyl-(3)-(2-bromo-ethyl)-(1)]- dithiophosphate (m.p.7880C).

Calc.: C, 30.08; H, 3.03; N, 7.02; P, 7.76; S, 16.06; Br, 20.02

Found: C, 30.19; H, 3.03; N, 7.06; P, 7.84; S, 16.00; Br, 20.12

EXAMPLE 19 a. As in Example 16, 344 g of vinyl acetate, 5.6 g of mercuryacetate, 0.75 g of sulfuric acid monohydrate and 85.3 g of6-chloro-oxazolo[4,5-b]pyridine-2- phoric acid are dissolved in 150 mlof toluene and boiled under reflux for 8 hours. The reaction mixture iscooled, diluted with ether, shaken out with sodium bicarbonate solutionand with water, dried, and the solvent distilled off. The residual oilcrystallises. Recrystallisation from 100 ml of methanol yields 61 g of0,0-diethyl-S-[6-chloro-oxazolo[4,'5-b]pyridin-2(3H)-onyl-(3)-ethy1-(1)]-dithiophosphate (m.p. 4547C).

Calc.: C, 37.65; H, 4.22; N, 7.31; 'P, 8.10; S, 16.75; Cl, 9.26.

Found: C, 37.39; H, 4.28; N, 7.41; P, 8.43; S, 16.79; Cl, 9.44.

EXAMPLE 20 v a. To a solution of 98 g of3-viny1-t-chlorooxazolo[4,5-b]pyridin-2(3H)-one and 0.2 g ofhydroquinone in 800 ml of carbon tetrachloride are slowly added dropwisewhile cooling with ice at -10C 80 g of bromine dissolved in 200 ml ofcarbon tetrachloride. The reaction mixture is filtered until clear andevaporated in a rotary evaporator. The crystalline residue is trituratedwith 300 ml of petroleum ether and filtered to yieldv 161 g of3-(1,2'-dibromoethy1)-6-chlorooxazolo[4,5-b]pyridin-2(31-I)-one (m.p.71-73C).

Calc.: C, 26.9; H, 1.4; Br, 44.9; Cl, 9.9; N, 7.8

Found: C, 26.1; H, 1.4; Br, 44.5; C1, 10.1; N, 8.5

b. 71 Grams of3-(1,2'-dibromoethy1)-6-chlorooxazolo[4,5-b]pyridin-2(31-1)-one and 48 gof the potassium salt of 0,0-diethyl-dithiophosphoric acid are dissolvedin 250 ml of acetonitrile and the solution is stirred for 4 hours. Thebulk of the solvent is then distilled off in a water jet vacuum and theresidue is treated with 300 ml of water. The oil that has separated outis taken up in ether, the ether solution is washed with sodiumbicarbonate solution and with water, dried, and the ether distilled off.86 Grams of a pale yellow, non-distillable oil are obtained, whichconsists largely of 0,0-diethy1-S-[6-chloro-oxazolo[4,5-b]pyridin-2(3H)-onyl-( 3 )-(2'-bromoethy1)-( 1 )-dithiophos- I Found: C, 31.9; H,3.4; Br, 16.3; C1, 7.7; N, 6.1; P, 6.7; S, 14.2

EXAMPLE 21 a. Proceeding in a manner analogous to that described inExample 17, 700 g of vinyl acetate, 1 ml of sulphuric acid monohydrateand 214 g of 6-bromooxazolo[4,5-b]pyridine-2(3H)-one are reacted underreflux. The reaction mixture is then filtered hot until clear and thefiltrate evaporated to dryness in vacuo. The residue is suspended inwater and filtered. 190 Grams of crude product are obtained.Recrystallisation from 1100 m1 of ethanol yields 147 g of 3-vinyl-6-bromo-oxazolo[4,5-b]pyridin-2(31-1-one (m.p. 110-112C).

Calc.:C,39.85;1-1, 2.08; Br, 33.2; N, 11.6

Found: C, 40.2; H, 2.1; Br, 32.8; N, 11.6

b. 38 Grams of 0,0-dimethyl-dithiophosphoric acid and 48 g ofvinyl-6-bromo-oxazolo[4,5-b]pyridin- 2(31-1)-one are dissolved in 120 mlof anhydrous ben-- zene and boiled under reflux for 8 hours. Thereaction mixture is cooled, diluted with ether and shaken out withsodium bicarbonate solution. The product is crystallised from the ethersolution, filtered and recrystallised from 900 m1 of methanol to yield56 g of 0,0- dimethyl-S-[6-bromo-oxazolo[4,5-b]pyridin-2(3H)- 20 onyl( 3)-ethyl-( 1 ]-dithiophosphate -117C).

Calc.: C, 30.08; H, 3.03; N, 7.01; P, 7.77; S, 16.06; Br, 20.02 Found:C, 30.18; H, 3.01; N, 7.01; P, 7.55; s, 16.17; Br, 20.21

EXAMPLE 22 a. To 240 g of vinyl acetate are added successively 3.6 g ofmercury acetate, 0.45 g of sulphuric acid monohydrate and 54 g of6-nitro-oxazolo[4,5-b]pyridin-2(3H)-one. The mixture is stirred for 2hours at 50C and the by now clear solution is concentrated in a rotaryevaporator. The crystalline residue is stirred with cold water,filtered, and the filtrate crystallised from 250 ml of ethanol to yield41 g of pale yellow 3-vinyl-6-nitro-oxazolo[4,5-b]pyridin-2(3H)-one(m.p. 107109C).

b. 38 Grams of 0,0-dimethyl-dithiophosphoric acid and 41 g of3-vinyl-6-nitro-oxazolo[4,5-b1pyridin- 2(3H)-one are reacted as inExample 21 b). Recrystallisation twice from m1 of methanol yields 19 gof 0,0-dimethyl-S-[6-nitrooxazolo[4,5-b]pyridin- 2(3H )-onyl-(3)-ethyl-( 1 )]-dithiopho sphate (m .p. l07-1 10C; mixed melting pointwith starting material 77-8 0C).

Calc.: C, 32.87; H, 3.31; N, 11.50; P, 8.50; S, 17.56 Found: C, 33.00;H, 3.45; N, 11.51; P, 8.18; S, 17.47

Compounds melting point 0,0-diethy1-S-[oxazolo[4 ,5-b]pyridin-2(3 H)- 38-39" ony1-(3)-methyl]-thiophosphate0.0-di-isopropyl-S-[oxazolo[4,5-b]pyridin-2- 61-63 (3H)-or1yl-(3)-methyl]-dithio-phosphate O,O-diallyl-S-[oxazolo[4,5-b]pyridin-2[3 1-11- 48-5 0 ony1-(3)-methylldithiophosphate Omethyl-S-[oxaz01o[4,5-b]pyridin-2(3 H)-ony'1- 95 97(3)-methyll-dithio-phenyl-phosphonatepyridin-2(3H)onyl-(3)-methyH-dithiophosiahate0,0-bis-(2-methoxy-ethy1)-S-[6-chloro-oxazolo- [4,5-b]pyridin-2(3H)-onyl-(3)-methyl]-dithio phosphate non-distillable oil0,0-diallyl-S-[6-chloro-oxazolo[4,5-b1pyridin- 28-292(31-1)-onyl-(3)-methy1]dithiophosphateO-ethyl-S-[6-chloro-oxazolo[4,5blpyridin-Z- 66-68 (31-1)-ony1-(3)-methyl]dithiophenylphosphonate0,0diethyl-S-[6-bromooxazolo[4,5blpyridin-Z- 5 860 (3H)-onyl-(3)-methyll-thiophosphate'O,O-bis-(2'methoxy-ethyl)S-[6-bromo-oxazolo non-distillable[4,5-b]pyridin-2(3 1-1)-ony1-(3)-methyl]-dithiooil phosphate 0,0-bis-(2chloro-ethyl)-S-[6-bromo-oxazolo 88-91 [4,5 43] pyridin-2(3H)-onyl-(3)-methyl]-dithio phosphate0,0-dimethyl-S-[oxazolo[4,5-b]pyridin-2(3 H)- 83-85 thione-3-yl-methyll-dithiophosphate O-ethyl-S-[6-chloro-oxazolo[4,5-b]pyridin-2-56-5 8 (3H)-onyl-(3)-methyl]dithio-methylphos-2(31-1)-ony1-(3)-methyl]-dithiophosphateO-methyl-N,N-dimethyl-S-[oxazolol4,5-blpyridin- 44-462(31-1)-ony1-(3)-methyll-dithiophosphorus amidate -continued Oethyl-N,N-dimethyl-S-[6-chloro-oxazolo[4,5-b] non-distillablepyridin-2(3 l1)-onyl-(3)-methyll-dithiophosoil 1 r phorus amidate0,0-dimethyl-S[oxazlo[4,5-b]pyridin-2(3 H)- non-distillableonyl-(3)-ethyl-(1 ')]-dithiophosphate oil0,0-dimethyl-S-[6-chloro-oxazolo[4,5-b]pyridin- 103 ,1 05

2(3 H)-onyl-(3)-ethyl-(l )1-dithiophosphate0,0-diethyl-S-[6-bromo-oxazolo[4,5-b]pyridin- 6870 2(3H)-onyl-(3)-ethyl-(1 )]-dithiophosphate0,0-diethyl-S-[oxazolo[4,5-b]PYridin-2(3 H)- 30.32

onyl-(3)-(2 '-bromo-ethyl)-(1 )]-dithiophosphate0,0diethyl-S-[6-nitro-oxazolo[4,5-b]pyridin- 103 105 2(3H)-onyl-(3)-ethyl-(1 ')]dithiophosphate *Calc. C 35.92 H 4.11 N 11.43 P8.44 5 17.44 C19,64% Found C 36.2 H 4,1 N 11,5 P 7.9 8 16,9 0w? 1 *Calc.C 37,49 H 4.09 N 8.75 P 9.69 S 20.02%

Found C 37.6 H 4.1 N 8 5 F 9,6 S 20.4%

Compounds melting point O-methyl-S-(oxazolo(4,5-b)pyridin-2(3H)-one-7476 3-y1-methyl)dithio-methylphosphonateO-ethyl-S-(oxazolo(4,5-b)pyridin-2(3 H)-one-3- non-distillabley1-methyl)-dithio-methylphosphonate oilO-methyl-S-(6-chloro-oxazolo(4,5-b)-pyridin- 5556 2(3H)-one-3-yl-methyl)-dithio-ethylphosphonate0,0-dimethyl-S-(oxazolo(4,5-b)pyridin-2(3 H)- 66-68one-3-y1-(2chIoroethyl)-(1))-dithiophosphate0,0-dimethyl-S(6-chloro-oxaz0lo(4,5-b)- non-distillable phyridin-2(3H)-one-3-yl-(2-bromoethyl)-(1))- oil dithio-phosphate0,0-dimethyl-S-(6-bromo-oxazolo(4,5-b)pyridinnon-distillable 2(3H)-one-3-yl-(2 -bromoethyl)-(l oil r dithio-phosphate "Calc. C 39.47 H4.31 N 9.21 P 10.18 S 21.08%

Found 39.5 4.6 8.8 10.3 20.8% alc. C 27.69 H 2.56 N 6.47 P 7.16 Cl 8,18Br 18.43%

Found 28.2 2.6 6.5 7.1 7.9 18.8% "**Calc. C 25.12 H 2.32. N 5.86 P 6.498 13.41 13: 33,4491.

Found 25.9 2.5 5.6 6.1 12.8 33.3%

EXAMPLE 23 548 Grams of 3-chloromethyl-6-chloro-oxazolo[4,5- b]pyridine-2(3H)-one, 480 g of the ammonium salt of0,0-dimethylmonophosphoric acid and 1200 ml of methanol are heated tothe boil as quickly as possible while stirring thoroughly and refluxedfor 5 minutes. The mixture is poured into 1800 ml of water and the bulkof the methanol is distilled off in a rotary evaporator. The initiallyoily precipitate congeals in the process to a crystalline state, isisolated by filtration and recrystallised from a mixture of 1200 ml ofmethanol and 300 ml of water, to yield 497 g of0,0-dimethyl-S-(6-chlorooxazolo(4,5-b)-pyridine-2(3H)-one-3-yl-methyl)-thiophosphate(m.p. 89-90C) Calc.: C, 33.29; H, 3.1 1 N, 8.63; P, 9.56; S, 9.88; Cl,10.92

Found: C, 33.56; H, 3.13; N, 8.52; P, 9.62 S, 9.78; C], 11.05

EXAMPLE 24 32 Grams of 3-(1',2'-dibromoethyl)-oxazo1o(4,5-b)pyridine-2(3H)-one are introduced into a solution of 19 g of theammonium salt of 0,0-dimethyl-dithiophosphoric acid in 50 ml of water.The mixture is stirred for one half hour at 6070C so vigorously that thefused dibromo compound is well emulsified. The oil layer congeals to acrystalline state on cooling and after recrystallisation yields 26 g ofO ,O-dimethyl-S-(oxazolo(4,5-b)-pyridin-2(3H)-one-3yl-(2-bromoethyl)-(1'))- dithiophosphate(m.p. 70-80C), which is identical with the compound of Example 18 (b).

EXAMPLE 25 22 Grams of 3-chloromethyl-6-chloro-oxazolo[4,5-b]pyridine-2(31-1)-one and 20 g of the sodium salt ofO-ethyl-thiophosphoric acid containing water of crystallisation arerefluxed for minutes in 50 ml of methanol. The solvent is distilled offin a rotary evaporator and on treating the residue with 100 ml of watera crystalline filling is obtained. Recrystallisation from 200 ml ofaqueous methanol yields 17 g of O-ethylS-(6chloro-oxazolo(4,5-b)pyridin-2(3H)-one-3-yl-methyl)- thiophosphoricamidate m.p. from 110C with decomp.).

Calc.: C, 33.39; H, 3.43; N, 12.98; P, 9.59; S, 9.91; C1, 10.95

Found: C, 33.72; H, 3.55; N, 12.91; P, 9.37; S, 9.89; Cl, 11.07

EXAMPLE 26 a. Proceeding in a manner analogous to that described inExamples 18(a) and 20(a), 3-(1 ,2'dibromoethyl)-6-bromo-oxazolo(4,5-b)pyridin- 2(3l-l)-one is manufacturedfrom 3-viny1-6-bromooxazolo[4,5-b]pyridin-2(3H) one (m.p. 8486C).

Calc.: C, 23.95; H, 1.25; Br, 60.0; N, 7.0

Found: C, 24.1; H, 1.2; Br, 59.6; N, 7.1

b. 40 Grams of3-(1,2'-dibromoethyl)-6-bromooxazo1o(4,5-b)pyridin-2(3H)-one and 24 g ofthe potassium salt of 0,0-diethyl-dithiophosphoric acid are suspended in50 ml of methanol and refluxed for 10 minutes. The solvent is thendistilled off in a rotary evaporator and the residue is treated with mlof water. The viscous oil that has separated out is taken up in ether,the ether solution washed with sodium bicarbonate solution and water,dried, and the ether distilled off. 51 Grams of0,0-diethyl-S-(6-bromo-oxazolo(4,5-b)pyridin-2(3H)-one-3-yl-(2'-bromoethyl)-(1))-dithiophosphate areobtained in the form of a pale yellow, viscous, non-distillable oil.

Calc.: C, 28. 47; H, 2.98; N, 5.54; P, 6.13; S, 12.67;

a. Chlorine gas is introduced while cooling with ice at 010C into asolution of 243 g of 3-vinyl-oxazolo[4,5-

.b]pyridin-2(3H)-one and 0.6 g of hydroquinone in 1500 ml of carbontetrachloride. The reaction solution is then filtered clear andconcentrated in a rotary evaporator. The initially oily residue isstirred with petroleum ether until it has thoroughly crystallised. Thecrystalline product is then filtered off and 220 g of 3-( 1,2'-dichloroethyl)-oxazolo(4,5-b) pyridin- 2(3H)-one are obtained (m.p.58-62C).

Calc.: C, 41.2; H, 2.58; CI, 30.47; N, 12.01

Found: C, 40.9; H, 2.6; Cl, 30.4; N, 12.0

By proceeding analogously, the two corresponding 3-(1',2'-dichl0roethyl)derivatives are obtained from3-vinyl-6-ch1oro-oxazolo[4,5-b]pyriclin-2(3H)-one and3-vinyl-6-bromo-oxazolo[4,5-b]pyridin-2(3H)-one; m.p. 60-64C and 73-75respectively.

Calc.: C, 30.8; H, 1.6; Br, 25.6; CI, 22.8; N, 8.98

Found: C, 31.6; H, 1.7; Br, 25.8; C1, 21.0; N, 9.1%.

b. 12 Grams of 3-(1,2'-dichlorethyl)-oxazolo (4,5- b)pyridin-2(3H)-oneare dissolved in 40 ml of methanol by gentle heating. 13 Grams of thepotassium salt of 0,0-diethyldithiophosphoric acid are dissolved in amixture of 10 m1 of water and 20 ml of methanol. The

23 two solutions are combined and left to stand for 24 hours at roomtemperature, in the process of which an oily and a crystallineprecipitate occur. The mixture is then heated briefly to 60C, the bulkof the methanol is evaporated off in a rotary evaporator, the residue istreated with water and extracted with ether. Recrystal- 24 The number ofAscaridia gallia rejected per test group over the course of 5 days afterthe first adminitration of active substance was determined daily and thenumber still found in the intestine of the 5th. day was likewisedetermined on dissection. Furthermore, the number of chicks free fromworms was determined.

Active substance Daily dosage Number of ascaridia of 5 chicks Number ofin mg per kg worm-free body weight chicks rejected during period foundof test on dissection absolute in of number total number0,0-di-isopropyl-S-[oxazolo[4,S-bl- 750 68 100 O 5pyridin-2(3H)onyl-(3)-methy11-dithiophosphate 0,0-bis-(2'-chloroethyl)S-[oxazolo 750 56 100 [4,5-b]pyridin-2(3 H)-onyl-(3)-methyl]-dithiophosphate 0,0-diethyl-S-[6-chloro-oxazolo- [4,5 b] 75 0 75 100 O 5pyridin-2(3H)-onyl-(3)-methyl]-dithiophosphate0,0-diethyl-S-[6-bromo-oxazolo-[4,5-b]- 750 82 100 O 5pyridin-2(3H)-onyl-(3)-methy1]-dithiophosphate lisation from 30 ml ofmethanol yields 13 g 0,0-diethyl- By proceeding in a manner analogous tothat de- EXAMPLE 30 Tests on mice infected with Syphacia obvel. andNematospiroides dubius Five mice each infected simultaneously withoxyurae (Syphacia obvel.) and trichostongylidae (Nematospiraides dubius)were freely fed with feed meal containing 0.2% of active substance. Themice were dissected on the 6th. day of the test and the number of wormspresent in the intestine was counted. Untreated mice that weresimultaneously infected in the same way were used for control purposes.

Active substance Daily dosage Total dosage Infection of test Infectionof the conin mg/kg in mg/kg animals on distrol animals on dissectionsection 0,0-diethyl-S-[oxazolo[4,5-b]-pyridin 208 1248 Syphacia abvel.Syphacia obvel.

2(3 H)-onyl-(3)methyll-dithiophosphate 0-0-0-0-0 1-1-2-4 Nematospir.dub. Nematospir. dub. 0,0-diethyl-S-[oxazolo[4,5-b]-pyridin- 0-0-0-0-06-8-8-10 2(3 H)-thione-3-yl-methyl]-dithiophosphate 175 1050 Syphaciaobvel. Syphacia obvel.

0-0-0-0-0 l- 1 -2-4 Nematospir. dub. Nematospir. dub. 0-0-0-0-0 6-88-10scribed in Example 14, 38 g of O-ethyl-e1th1o-ethyl- EXAMPLE 31phosphonic acid are reacted with 44 g of 3-chloromethyl-6-chloro-oxazolo[4,5-b]pyridine-2(3H)-one.36 Grams ofO-ethyl-S-(6-chloro-oxazolo(4,5-b)pyridin-2(3H)-one-3-yl-methyl)-dithioethylphosphonate are obtained (m.p. 42C).

Calc.: C, 37.44; H, 4.00; CI, 10.65; N, 7.94; S, 10.18; P, 8.77

Found: C, 37.28; H, 4.15; CI, 10.22; N, 8.04; S, 17.96; P, 8.66

EXAMPLE 29 Determination of the anthelminthic action in hens infectedwith Ascaridia galli 1 to 3 days old chicks are artificially infectedwith eggs of Ascaridia galli (roundworms). Groups of chicks each wereused per test. Four to five weeks after the chicks had been infected,the active substances were administered in one dose per day on 3successive days. Infected chicks that were not treated were used forcontrol purposes.

Evaluation:

a. Insecticidal contact poison action Active substance Flies MosquitoesStable flies 0.0-dimethyl-S(0xazolo(4,5-b))- 24' 10pyridin-2(3H)-one-2-yl-methyl)- dithiophosphate0,0-dimethyl-S-(oxazolo(4,5-b))- 2' 60 30 pyridin-2(3H)one-3-ylether(l))-dithiophosphate continued Active substance Flies Mosquitoes Stableflies 0,0-diethyl-S-(oxazolo(4,5-b)- 2" 60 30 pyridin-Z(3H)-one-3-yl-ethyl-l 1 1 dithiophosphate 0,0-diethyl-S-(oxazolo(4,5-b))-5'' 2' 2' pyridin-2(3 I-I)-one-3-yl-(2 ethyD-(l '))-di-thiophosphate0,0-dimethyl-S-(oxazolo(4,5-b))- 6O 10 2(3 H)one3-y1methyl)-thiophosphate 0,0-diethyl-S-(oxazolo(4,5-b))- 5 90'pyridin-2(3H)-one-3-ylmethyl)- thiophosphate 0,0-dimethyl-S-(6-chloro-24' 8" 30 a 20 mg of a 1% dusting agent are uniformly distributed inPetri dishes. The dishes are then filled with cockroaches (,Phyllodromiagermanica and Periplaneta americana) and kept under normal conditions atThe following table indicates theftime after which all animals are inthe dorsal position. y

Insecticidal contact poison action against cockro aches:

0,0-dimethyl-S(6-chloro-(oxazolo(4,5b))-Pyridin 4"2(3l-l)-one-3-yl-methyl)-dithiophosphate0,0-dimethyl-S(6-bromo-(oxazolo(4,5-b))-Pyridin- 90 2(3H)-one-yl-methyl)-dithiophosphate0,0-dimethyl-S(oxazolo(4,5-b)-Pyridin-2(3I-l)-one-3- 55yl-methyD-thiophosphate0,0-dimethyl-S-(6-chloro-(oxazqlo(4,5-b))-PYIidin- 2(3H)-one-3-yl-methyl)-thiophosphate0,0-dimethyl-S(6-bromo(oxazolo(4,5-b))-pyridin- 2(3H)-one-3-yl-methyl)-thiophosphate I0,0-diethyl-S-(6-chloro-(oxazolo(4,5-b))-pyridin- 47 2(3H)-one-3-yl-methyl)-thiophosphate O ,O-diethyl-S(6-bromo-(oxazolo(4,5-b))-pyridin- 5 7 2(3 I-l)-one-3-yl-methyl)-thiophosphate O,O-dimethyl-S-(oxazolo(4 ,5-b))-pyridin-2(3 H)-one-3- yl-ethyl(l))-eithiophosphate 0,0-diethyl-S(oxazolo(4,5-b))-pyridin-2(3l-I)-one-3-yl- 4" (2 bromoethyl)-(l ))-dithio-phosphate O ,O-diethyl-S-(6-chloro-(oxazolo(4 ,5 -b))-pyridin-2 (3 H)- 5 one-3-yl-ethyl-(l))-dithio-phosphate O-methyl-S-(6-chloro-(oxazolo(4,5-b))-pyridin-2(3H)- 95 one-3-yl-methyl)-dithiometh yl-phosphate O-ethyl-S(6-chloro(oxazolo(4,5-b))-pyridin-2(3 H)-one- 3-yl-methyl)-dithiomethylphosphatea Grain weevils are sprayed with 2 ml of 1% acetonic active substancesolution from a distance of 10 cm by means of a spray jet. Immediatelyafter the application the weevils are transferred to clean Petri dishesand kept at 22C. The following table indicates the time after which allthe weevils are in the dorsal position.

Insecticidal contact poison action against grain weevils0,0-dimethyl-S-(oxazolo(4 ,5 -b))-pyridin-2(3 I-l)-one-3- 3"yl-methyl)-dithiophosphate O ,O- di'methyl-S-(oxazolo(4 ,5-b))'-pyridin-2 (3 H)-one-3- 60 yl-methyD-thiophosphate0,0-dimethyl-S-(oxazolo(4,5-b))-pyri in-2(3 l-l)-one-3- 60 yl-ethyl-(l))-dithiophosphate 0,0-dimethyl-S-(6-chloro-(oxazolo(4 ,5 -b))-pyridin-30 2(3 I-I)-one-3-yl-methyl)-thiophosphate O,O-diethyl-S-(6-chloro-(oxazolo(4 ,5-b))-pyridin-2(3 I-l)- I00one-3-yl-methyl)-thiophosphateO-ethyl-S(6-chloro-(oxazolo(4,5-b))-pyridin-2(3 l-l)-one- 2" 3-yl-methyl)-dithi0-methylphosphonate0,0-dimethyl-S-(6-bromo-(oxazolo(4,5-b))-pyridin- 30 2(3I-I)-one-3-yl-methyl)-thiophosphate 0,0-diethyl-S-(6-bromo-(oxazolo(4 ,5-b))-pyn'din-2(3 H)- 100 one-3-yl-methyl)-thiophosphate b. Insecticidalperiod of activity a. on glass: Petri dishes with active substance.

coatings of 1 g of active substance per m are left to stand for 8 daysat 24C. Then polyvalent resistant houseflies, mosquitoes and stableflies are placed on the coatings.

b. on wood: the active substances are applied to small planks of wood ina concentration of 1 g of active substance per m from aqueoussuspension. After 8 days the above mentioned test subjects are placed onthe planks. The following table indicates the time in hours after whichthe test subjects are in the dorsal position.

Glass 8 days Wood 8 days flies mosquitflies mosstable oes quitflies oes0,0-dimethyl-S-(oxazolo-(4,5-b))Pyridin- 5 60 60 90 90' 2(3 H)-one-3yI-methyD-thiophosphate 0,0diethyl-S-(oxazo1o(4,5-b))Pyridin- 4" 55 5 902(3 I- I)-one-3-yl-methyD-thiophosphate0,0-d|methyl-S-(oxazolo(4,S-bDPYridin- 5 30 30 5 90 60 2(3l-l)-one3-yl-ethyl-(l ')-dithiophosphate0,0-diethyl-S-(oxazolo(4,5-b))pyridin- 5 h 30' 10 5 60 30 2-(3H)-one-3-yl-ethyl-(l '))-dithiophosphate 10,0-dimethyl-S-(6-chloro-(oxazolo- 5 I00 (4 ,5 -b))pyridin-2(3l-l)-one-3-ylmethyl)-dithiophosphate O,O-dimethyl-S-(-chloro-(oxazolo- 52' 60 5 30' (4,5-b))PYridin-2(3 H)-one-3-ylmethyD-dithiophosphate0-ethyl-S(6-chloro (oxazolo(4,5-b))- 5 2" 30 2" 60' 60 pyridin-2(3I-l)-one-3-yl-methyl)- dithio-methylphosphonate.

-c ontinued Glass 8 days Wood 8 days flies mosquitflies mosstable oesquitflies A oes (4,5-b))pyridin-2(3 I-l)-one-3-ylmethyl)-thiophosphate0,0-diethyl-S-(6-bromo-(oxazolo- 5' 90' 2' 5 30 (4,5 -b))pyridin-2(3H)-one-3-ylmethyl)-thiophosphate 0,0-diethyl-S-(oxazolo(4,5-b))pyridin-5 60' 30 2' 5 c. Systematic inseticidal action To determine thesystematic action, 50 ml of an aqueous emulsion containing 100 ppm ofactive substance (obtained from a 10% emulsifiable concentrate) ispoured onto the earth of bean plants in pots per 600 cm After 3 days,aphids (Aphis fabae) are placed on the portions of the plants above thesoil. The aphids are protected by a special device from the contact andgas action. The test is carried out at 24C and 70% relative atmospherichumidity.

The following table indicates the time in days after which 100% of theaphids are in the dorsal position.

Days

' 0,0-dimethyl-S-(oxazolo(4,5-b))-pyridin-2(3 H)-0ne-3- 3 yl-ethyl-( l))-dithiophosphate 0,0-diethyl-S-(oxazolo(e ,5 -b))-pyridin-2(3H)-one-3-yl- 3 ethyl-(l ))-dithiophosphate O.0-diethyl-S-oxazolo(4,5-b))-pyridin-2(3H)-one- 3-yl- 1 Iethyl-(l))-dithiophosphate 0,0-dimethyl-S-(oxazolo(4,5-b))-pyridin-2(3H)-one-3- 3 3 5 yl-methyl)-thiophosphate0,0-diethyl-S-(oxazolo(4,5b))-pyridin-2(3 H)-one-3-yllmethyl)-thiophosphate 0,0-bis-(2 -methoxy-ethyl)-S-(oxazolo(4 ,5-b))PYridin- 2(3 H)-one-3-yl-methyl)-dithiophosphate O-methyl-N,N-dimethyl-S-(oxazolo(4 ,5 -b))-pyridin-2(3H)-one-3-yl-methyl)-dithio-phosphorus amidate0.0-dimethyl-S-(6-bromo-(oxazolo(4,5-b))-pyridin- 2(3H)-one-3-yl-methyl)-thiophosphate WNUJ d. Insecticidal ingested poisonaction Potato plants are dipped in a 0.1% aqueous active substanceemulsion (obtained from 10% emulsifiable concentrate). After the coatinghas dried, larvae of the colorado potatoe beetle (Leptinotarsadecemlineata) are applied to the plants.

The following table indicates the times in minutes and hours after whichall beetles (100% are in the' dorsalt position.

0,0-dimethyl-S(oxazolo(4,5-b))pyridiri-one-B-yl-methybdithiophosphate0,0-dimethyl-S-(oxazolo(4 ,5 -b))pyridin-2(3 H)-one-3-ylethyl-(1))-dithiophosphate 0,0-dimethyl-S-(oxazolo(4,5-b))-pyridin-2(3H)-one-3-yl- 60 (2 -bromoethyl)-(l ))-dithiophosphate0,0-diethyl-S-(oxazolo(4,5-b))-pyridin-2(3 H)-one-3-yl- 5 0 (2bromoethyl)-(1 ))-dithiophosphate 600,0-diethyl-S-(oxazolo(4,5-b))pyridin-2(3H)-one-3-ylmethyD-thiophosphate 0,0-bis(2 '-chloroethyl)-S-(oxazolo(4 ,5-b))-pyridin- 2' 2(3 H)-one-3-yl-methyl)-dithiophosphate0,0-dimethyl-S-(6-chloro(oxazolo(4,5-b))-pyridin-2(3 H)- 60'one-3-yl-methyl)-thiophosphate0,0-diethyl-S-(6-chloro(oxazolo(4,5-b))-pyridin-2(3 H)- 50' 6 5one-3-yl-methyl)-thiophosphate0,0-diethyl-S-(6-chloro-(oxazolo(4,5-b))-pyridin-2(3 I-l)- 60one-3-yl-ethyl-(I ))-dithiophosphate0,0-diethyl-S-(6-chloro-(oxazolo(4,5-b))-pyridin-2(3 H)- 90 one-3-yl-(2bromoethyD-(l ))-dithiophosphate0,0-diallyl-S-(6-chloro-(oxazolo(4,5-b))-pyridin-2(3 H)- 4"one-3-yl-methyl)-dithiophosphateO-ethyl-S(6-chloro-(oxazolo(4,5-b))-pyridin-2(3 H)-one-3- 5yl-methyl)-dithiophenylphosphonateO-methyl-S-(6-chloro-(oxazolo(4,5-b))-pyridin-2(3 H)- 60one-3-yl-methyl)-dithiomethyl-phosphonateO-methyl-N,N-dimethyl-S-(6-chloro-(oxazolo(4,5-b))- 2'pyridin-2(3H)-one-3-yl-methyl)-dithio phosphorus amidate0,0-diethyl-S-(6-bromo(oxazolo(4,5-b))-pyridin-2(3 l-l)- 20one-3-yl-methyl)-thiophosphate O ,0-dimethyl-S-(6-bromo-(oxazolo(4 ,5-b))-pyridin- 60 2(3 l-l)-one-3-yl-ethyl-(l ')-dithiophosphate0,0-dimethyl-S-(6-nitro-(oxazolo(4,5-b))-pyridin-2(3 H)- 60one-3-yl-methyl)-dithiophosphate O ,O-diethyl-S-(-nitro- (oxazolo (4,5-b))-pyn'din-2 (3 H)- 60 one-3-yl-methyl)-dithiophosphate0,0-diethyl-S-(6-nitro-(oxazolo(4,5-b))-pyridin-2(3i-l)- 60one-3-yl-ethyl-(l ))-dithiophosphate0,0-dimethyl-S-(oxazolo(4,5-b))-pyridin-2(3H)-thione- 53-yl-methyl)-dithiophosphate EXAMPLE 32 Acarjcidal action a. Actionagainst mites (Tetranychus urticae) To test the acaricidal action, beanleaves that are attacked by adults, encystments and eggs of the redspider mite (Tetranychus urticae) are treated with an aqueous emulsioncontaining the test substance in a concentration of 0.1 The testsubjects are strains of the red spider mite that are resistant tocommercially available phosphorus esters.

Mortality in within 6 days at an active substance concentration of 0.l

Active substance pyridin-2(3H)-on-3-yl-ethyl-( l '))-dithiophosphate 2930 -continued -continued Active substance Mortality in Active substanceTickovi- Hatchwithin 6' days at strain posiing an active substance tionrate concentration of 0.l.% Adults 5"- Eggs0,0-dimethyl-S-(6-chloro-(oxa- Ridgeland 0 yzolo(4,5-b))pyridin-2(3H)-onemems 3-yl-methyl)-thiophosphateO-methyl-S-(6-chloro-(oxazolo- Biarra 00,0-dimethylS-(oxazolo(4,5-b))-pyndin- 100 57 63 4,5 .2 3m-one-sl-2(3H)-thione-3-yl-methyl)-dithiomethyl)-dithiomethyl-phosphosphatephonate 0.0- i et y -S( x zc -b))-py 100 1 1000,0-dimethyl-S-(6-bromo-oxa- Ridgeland 02(3l-l-one-3-yl-methyD-thiophosphate zolo(4,5-b))pyridin-2(3I-l)-one- O,O-dimethyl-S-(6-chloro(oxazolo(4,5-b)) 100 100 1003-yl-methyl)-dithiophosphatepyridin-2(3H)-one-3-yl-methyl)-thiophosphate l50,0-dimethyl-S-(6-bromo-(oxazolo(4,5-b)) 100 100 100pyridin-2(3l-l)-one-3-yl-methyl)-thio phosphate What we claim is:O-methyl-S-(oxazolo(4,5-b))pyridin- 100 100 100 2(3H) One 3 yl methyl)dithiomethyl ll oxazolo[4,5 blpyridme compound of the for phosphonate mua O-ethyl-S-(oxazolo(4,5-b))pyridin-2(3H)- 100 100 100one-3-yl-methyl)-dithiomethylphosphonate 0O-methyl-S-(6-chloro-(oxazolo(4,5-b))- 100 100 100 Rpyridin-2(3l-l)-one-3-yl-methyl)-dithio- 1 In) ethylphosphonate l C XO-ethyl-S-(6chlor0-(oxazolo(4,5-b))- 100 100 100pyridin-2(3l-l)-one-3-yl-methyl)-dithio- N N ethylphosphonate l A b.Action against ticks (Boophilus microplus) 10 Adults, egg laying ticksof various strains are wherein I dipped for 3 minutes in an aqueousemulsion of active A represents a halogenomethyl, the vmyl or asubstance in a concentration of 0.1 The ticks are 1,2-dihalogenoethylgroup, then kept at 27C and 80% relative atmospheric humid- R ishydrogen, halogen or nitro, and ity. On the 5th., 10th. and 15th. day,oviposition is X represents oxygen or sulphur. determined. The eggs arekept for a further 20 days I under the same conditions and the possiblehatching 2- A o p acccrdmg t0 clalm 1 m whlch 1 is rate determined.hydrogen, fluorine, bromine or nitro. 1

3. The compound according to claim 2 which is 3- Acfivesubstance TickOVL "amp chloromethyl-oxazolo[4,5-bl pyr1d1n-2(3I-l)-one.

main ing 40 4. The compound according to claim 2 which 18 3- tion W 7chloromethyl-o-bromo-oxazolo-pyridin-2(3l-l)-one. 00 h l 5. The compoundaccording to claim 2 which is 3- iet yoxazo o(4,5-b))- ridin- Rid eland0 2(3H) ne 3 yl methyl) dithio%os g chloromethyl--bromo-oxazolo-[4,5-b]pyridm orgia t l 2(3l-l)-one.

Ormal o 6. The compound according to claim 2 which is 3- otgtilo-fihlusphate chloromethyl-oxazolo[4,5-b]pyrrdm-2(3H)-th1one.

5 }.15$ g gffiggfifgifliggl i 0 7. The compound according to claim 2which is 3- l hi ph ph te chloromethyl-6-nitro-oxazolo-[4 ,5 -b]pyridin- 0,0-diethyl-S-(oxazolo(4,5-b))- Biarra 0 2 3Hpyridin-2(3l-l)-one-3:yl-(2- YD-( ))-d|thio- 8. The compound accordingto claim 2 which is 3- phosphate ,0-dimethyl-S-(oxazolo(4 ,5 -b))-Biarra 0 vmyl'oxazolo 4,5 ]Py 3 H 9. The compound according to claim 2which is 3- methyD-thro-phosphate 0.0-bis-(2-methoxa-ethyl)-S- Ridgelando y aZ lp (oxazolo(4,5-b))pyridin-2(3H)- 2(3l-l)-one.one-3-yl-methyl)-dithiophosphate 10. The compound according to claim 2which is gg Ridseland 03-vinyl-6-chloro-oxazolo[4,'5-b]pyridin-2(3l-l)-one.

methyb-dithiophosphat 11. The compound according to claim 2 which is0.0-dimethyl-S-(6-chloro(oxazolo- Ridgeland 0 3-( l',2'-dibromo-ethyl)-6-chloro-oxazolo[4,5-b1pyri- 4.s-b) )py riqi-2om-ene-a-yldin-2(3l-l)-one. g qz t 'f tg zi l 12. The compoundaccording to claim 2 which is g jg ggggggfg f Ridgeland 03-vinyl-6-bromo-oxazolo[4,5-b]pyridin-2(3H)-one. methyD-dithiophmphate13. The compound according to claim 2 which is0,0idimethyl-s-(o-chloro-(oxa- Biam o3-vinyl-6-nitro-oxazolo[4,5-b]pyridin-2(3H)-one.

"."7 14. The compound according to claim 2 which is -y-ethyl-(l))-dithrophosphate I O,odiethy].S (6 chlm (xa Bima 0 3-(l ,2-dibromo-ethyl)-6-bromo-oxazolo[4,5-b]pyrtzolo-(4,5-b))pyridin-2(3H)-one-3-yl-ethyl-(l ))-dithiophosphate 0,0-dimethyl-S(6-chlcro-(oxazolo-(4,5-b))pyridin-2(3 H)-one-3-ylmethyl)-thiophosphate Biarra normal 0din-2(3l-l)-one.

15. The compound according to claim 2 which is 3-( l,2'-dichloroethyl)-oxazolo[4,5-b]pyridin- 2(3H)-one.

16. The compound according to claim 2 which is 17. The compoundaccording to claim 2 which is 3-( l',2'-dichloro-ethyl)-6-chloro-oxazolo[4,5-b1pyri- 3:( l ',2-di h] r hl)ggm din-2(3H)-one. dm-ZQI-Iym v

1. AN OXAZOLO(4,5-B)PYRIDINE COMPOUND OF THE FORMULA 111
 2. A compoundaccording to claim 1 in which R1 is hydrogen, fluorine, bromine ornitro.
 3. The compound according to claim 2 which is3-chloromethyl-oxazolo(4,5-b)-pyridin-2(3H)-one.
 4. The compoundaccording to claim 2 which is3-chloromethyl-6-bromo-oxazolo-pyridin-2(3H)-one.
 5. The compoundaccording to claim 2 which is 3-chloromethyl-6-bromo-oxazolo-(4,5-b)pyridin-2(3H)-one.
 6. The compound according to claim 2 which is3-chlorOmethyl-oxazolo(4,5-b)pyridin-2(3H)-thione.
 7. The compoundaccording to claim 2 which is3-chloromethyl-6-nitro-oxazolo-(4,5-b)pyridin-2(3H)-one.
 8. The compoundaccording to claim 2 which is 3-vinyl-oxazolo(4, 5-b)pyridin-2(3H)-one.9. The compound according to claim 2 which is3-(1'',2''-dibromo-ethyl)-oxazolo-(4,5-b)pyridin-2(3H)-one.
 10. Thecompound according to claim 2 which is3-vinyl-6-chloro-oxazolo(4,5-b)pyridin-2(3H)-one.
 11. The compoundaccording to claim 2 which is3-(1'',2''-dibromo-ethyl)-6-chloro-oxazolo(4,5-b)pyridin-2(3H)-one. 12.The compound according to claim 2 which is3-vinyl-6-bromo-oxazolo(4,5-b)pyridin-2(3H)-one.
 13. The compoundaccording to claim 2 which is3-vinyl-6-nitro-oxazolo(4,5-b)pyridin-2(3H)-one.
 14. The compoundaccording to claim 2 which is3-(1'',2''-dibromo-ethyl)-6-bromo-oxazolo(4,5-b)pyridin-2(3H)-one. 15.The compound according to claim 2 which is3-(1'',2''-dichloro-ethyl)-oxazolo(4,5-b)pyridin-2(3H)-one.
 16. Thecompound according to claim 2 which is3-(1'',2''-dichloro-ethyl)-6-chloro-oxazolo(4,5-b)pyridin-2(3H)-one. 17.The compound according to claim 2 which is3-(1'',2''-dichloro-ethyl)-6-bromo-oxazolo(4,5-b)pyridin-2(3H)-one.